Protect revealjs processing by warning about any internal id used in the document

Bug description

When a div with #title-slide is present in the document (used to horizontally center text https://github.com/quarto-dev/quarto-cli/issues/1231) and hash-type is set to number, the title on the title slide is top-aligned instead of vertically centered. Removing hash-type: number reverts the expected behaviour.

Steps to reproduce

---
title: "What a Great Title"
format:
  revealjs:
    hash-type: number
    center-title-slide: true
---

## This Slide Is Perfect

:::{#title-slide}
Profound statement
:::

Expected behavior

The title on the title slide should be vertically centered

Actual behavior

The title on the title slide is top-aligned

Your environment

• OS: macOS Sonoma 14.6.1
• IDE: Positron
  • Version: 2024.09.0 (Universal) build 1
  • Code - OSS Version: 1.92.0
  • Commit: f37f4f5044a2a619e73d5db61a31e37fbd3faf18
  • Date: 2024-09-03T02:37:20.474Z
  • Electron: 30.1.2
  • Chromium: 124.0.6367.243
  • Node.js: 20.14.0
  • V8: 12.4.254.20-electron.0
  • OS: Darwin arm64 23.6.0

Quarto check output

Quarto 1.5.55
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.2.0: OK
      Dart Sass version 1.70.0: OK
      Deno version 1.41.0: OK
      Typst version 0.11.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.5.55
      Path: /Applications/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: (external install)
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /Users/gleb/Library/TinyTeX/bin/universal-darwin
      Version: 2024

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.12.5
      Path: /Users/gleb/.pyenv/versions/3.12.5/bin/python3
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

[✓] Checking R installation...........OK
      Version: 4.4.1
      Path: /opt/homebrew/Cellar/r/4.4.1/lib/R
      LibPaths:
        - /Users/gleb/Library/R/arm64/4.4/library
        - /opt/homebrew/lib/R/4.4/site-library
        - /opt/homebrew/Cellar/r/4.4.1/lib/R/library
      knitr: 1.48
      rmarkdown: 2.28

[✓] Checking Knitr engine render......OK